Allergenic Weeds of Southern California

Pollen allergens with hyperlinks are available in GREER's catalog. Click on the allergen that you are interested in and connect with that item in GREER's catalog.

To learn more about a particular pollen allergen, click on the PDF icon [] of that allergen. These botanical profiles are available for download and include a detailed profile, genus/species and family, location(s) found in the United States and photograph(s) of the pollen.

Marked Cells () signify taxon present in area. Unmarked Cells signify taxon absent in area or unconfirmed.

1 Cross-reactive species grouped together in colored cells
2 Italicized species demonstrate only moderate cross-reactivity with other(s) in the group
3 This species is insect-pollinated

Most weeds pollinate in the fall.

	Coastal					Inland Empire			Central Valley			Low Desert
Cross-Reactive Weeds 1
202: Allscale		x	x	x		x	x		x	x		x
240: Lenscale/Quailbrush	x	x	x	x		x	x		x	x		x
206: Wingscale :		x	x	x		x	x			x		x
49: Palmer's Amaranth		x		x		x	x			x		x
32: Careless Weed		x		x
52: Pigweed, Rough/Redroot :	x	x	x	x			x			x
40: Hemp, Water		x		x
35: Dock, Yellow/Curly :	x	x	x	x		x	x			x
64: Sorrel, Sheep/Red :	x	x	x	x		x	x		x	x
Jerusalem Oak	x	x	x			x			x	x
43: Lamb's Quarter :	x	x	x	x		x	x			x		x
Mexican Tea	x	x	x	x		x	x		x	x
48: Mugwort, Darkleaved :			x	x		x	x		x	x
Wormwood, Annual									x	x
268: Sagebrush, Coast :	x	x	x	x			x		x	x
61: Sagebrush, Common :		x	x	x		x	x		x	x
272: Ragweed, Desert :				x		x	x			x		x
185: Ragweed, False :	x	x	x	x		x	x		x	x
55: Ragweed, Giant :	x
56: Ragweed, Short :		x	x
50: Ragweed, Slender	x	x	x	x		x
58: Ragweed, Western :	x	x	x	x		x	x
Other Weeds
225: Baccharis :	x	x	x	x		x	x		x	x		x
213: Burrobrush :		x	x	x		x	x			x		x
33: Cocklebur :	x	x	x	x		x	x		x	x		x
37: Goldenrod 3 :	x	x	x	x		x	x		x	x		x
212: Iodine Bush :		x		x		x	x		x	x		x
42: Kochia/Firebush :	x	x	x	x								x
36: Nettle :	x	x	x	x		x	x		x	x
54: Plantain, English :	x	x	x	x		x	x			x
Poverty Weed	x	x	x	x		x	x		x	x
59: Russian Thistle :	x	x	x	x		x	x			x

Data obtained from USDA Plants Database.

For current pollen counts visit www.pollen.com or enter a zip code below.

Please enable pop-up windows in your browser to use this feature.